Computer Science Question

Description

Assignment due Friday, November 1, 2024 by 11:00pm

Part 1: Theory (LO1, LO2, LO5)

Answer the following questions. For all answers, ensure there is sufficient description to justify your answer and the work done to get the answer.

A. Application Layer Concepts (Layer 7):

1. In your own words, explain the purpose and functions of the Application Layer in the OSI model.
2. In your own words, list and describe briefly 4 Internet applications including stating the application layer protocol, RFC number and the transport protocol used.
3. In your own words, discuss the differences between P2P and Client-Server architectures including how to calculate the file distribution time.

B. Transport Layer Concepts (Layer 4):

1. In your own words, describe the purpose and functions of the Transport Layer in the OSI model.
2. In your own words, explain the concept of port numbers and how they facilitate end-to-end communication.
3. In your own words, discuss the differences between TCP and UDP in terms of connection-oriented vs. connectionless communication and in terms of the headers used.

C. Consider the scenario below and answer the questions.

1. What layer in the IP stack best corresponds to the phrase: ‘moves datagrams from the source host to the destination host’?
2. What layer in the IP stack best corresponds to the phrase: ‘handles messages from a variety of network applications’?
3. What layer in the IP stack best corresponds to the phrase: ‘handles the delivery of segments from the application layer, may be reliable or unreliable’?
4. Explain which layer corresponds to box 1, 2, 3, 10, 13, 14, and 15?

D. Consider the figure below, where the server is sending a HTTP RESPONSE message back the client and answer the questions.

Suppose the server-to-client HTTP RESPONSE message is the following:

HTTP/1.0 200 OK

Date: Sat, 28 Sep 2024 19:43:27 +0000

Server: Apache/2.2.3 (CentOS)

Last-Modified: Sat, 28 Sep 2024 19:54:27 +0000

ETag:17dc6-a5c-bf716880.

Content-Length: 362

Connection: Close

Content-type: text/html

1. Is the response message using HTTP 1.0 or HTTP 1.1?
2. Was the server able to send the document successfully? Yes or No
3. How big is the document in bytes?
4. What is the type of file being sent by the server in response?
5. What is the name of the server and its version? Write your answer as server/x.y.z?

E. Consider the figure below and answer the following questions.

TCP sender and receiver communicate over a connection in which the sender->receiver segments may be lost. The TCP sender sends an initial window of 4 segments. Suppose the initial value of the sender->receiver sequence number is 86 and the first 4 segments each contain 145 bytes. The delay between the sender and receiver is 7 time units, and so the first segment arrives at the receiver at t=8. As shown in the figure below, 0 of the 4 segment(s) are lost between the segment and receiver.

1. Give the sequence numbers associated with each of the 4 segments sent by the sender. Format your answer as: a,b,c,…
2. Give the ACK numbers the receiver sends in response to each of the segments. If a segment never arrives use ‘x’ to denote it, and format your answer as: a,b,c,…

F. Consider the figure below and answer the following questions.

Three hosts, with private IP addresses 10.0.1.12, 10.0.1.16, 10.0.1.23 are in a local network behind a NAT’d router that sits between these three hosts and the larger Internet. IP datagrams being sent from, or destined to, these three hosts must pass through this NAT router. The router’s interface on the LAN side has IP address 10.0.1.28, while the router’s address on the Internet side has IP address 135.122.196.212.

1. Consider the datagram at step 1, after it has been sent by the host but before it has reached the router. What is the source IP address for this datagram?
2. At step 1, what is the destination IP address?
3. Now consider the datagram at step 2, after it has been transmitted by the router. What is the source IP address for this datagram?
4. At step 2, what is the destination IP address for this datagram?
5. Will the source port have changed? Yes or No.
6. Now consider the datagram at step 3, just before it is received by the router. What is the source IP address for this datagram?
7. At step 3, what is the destination IP address for this datagram?
8. Consider the datagram at step 4, after it has been transmitted by the router but before it has been received by the host. What is the source IP address for this datagram?

G. Consider the figure below and answer the following questions.

There is a router and the two attached subnets below (A and B). The number of hosts is also shown below. The subnets share the 24 high-order bits of the address space: 192.168.72.0/24

1. Is the address space public or private?
2. How many hosts can there be in this address space?
3. What is the subnet address of subnet A? (CIDR notation)
4. What is the broadcast address of subnet A?
5. What is the starting address of subnet A?
6. What is the ending address of subnet A?
7. What is the subnet address of subnet B? (CIDR notation)
8. What is the broadcast address of subnet B?
9. What is the starting address of subnet B?
10. What is the ending address of subnet B?

Part 2: Network Design and Configuration using Packet Tracer (LO1, LO2, LO3, LO5)

XYZ is a fast-growing company with many branches and customers. As a network administrator you have been asked to configure the XYZ company network. All devices in all the departments are required to communicate with each other and on the Internet.

The company has 3 departments:

1. Operations
2. Production
3. Admin

Using packet Tracer and the provided topology please complete the following tasks:

Configure Device Basic SettingsConfigure RIPv2 Dynamic Routing ProtocolTest the connectivity to demonstrate how these devices can communicate without connectivity issues and if there are any issues then please troubleshoot them. Provide evidence in your report including troubleshooting any issues (screenshots).Configure one or more application layer services (e.g., Web server or FTP server) on a computer in one of the departments (self-study)Test to demonstrate how these services communicate between devices, using specific port numbers and if there are any issues then please troubleshoot them. Provide evidence in your report including troubleshooting any issues (screenshots).Document your configuration file (running-config) and include it in your assignment report.

Submission Details

1. Documentation:

a. Prepare a report that covers answers to all parts and tasks including explanations and justifications.

b. Name the report “first name _ Student ID _ A2Report.pdf”:

Example: “Amjad_202312345_A2Report.pdf”.

c. Save your Packet Tracer file using your first name and your student ID “first name_ Student ID_A2.pkt”:

Example: “Amjad_202312345_A2.pkt”

1. Files to submit:

· Primary resource: The report (pdf file) “first name _ Student ID _ A2 Report.pdf”

· Secondary resource: A zipped/compressed folder of the Packet Tracer file and all the screenshots that you have taken to support your report documentation.

· Both resources must be submitted. Order of resource submission is important i.e., packet tracer file cannot be primary resource. If files are not submitted correctly a maximum of 2 would be the grade.

1. Assessment:

· Assessment will be based on the accuracy and completeness of the report, the quality of the documentation, and the ability to effectively explain the integration of the Network and Transport Layers.

Assignment Information

Weight:

20%

Learning Outcomes Added

• LO1_Components: Explain computer network components, including end systems, switching devices, communication mediums, protocols, and applications.
• LO2_Models: Describe reference models, addressing and subnetting, switching techniques, and routing algorithms and protocols.
• LO3_Design: Design a network (VLANs) to support and realize an enterprise use case
• LO5_Protocols: Compare various communication protocols to meet application layer requirements.